1,720,959 research outputs found
Mechanically ventilated classrooms in central Italy's heritage school buildings: Proposal of archetypes and CO2 prediction models
No full textThis study proposed a typological analysis to identify the archetypes of classrooms equipped with controlled mechanical ventilation (CMV) in Italy and an experimental campaign on 58 typical classrooms to identify the main indoor microclimatic characteristics and CO2 concentrations. From the analyses carried out, general information was gathered on the heating systems and the main energy and acoustic improvements carried out in the schools. The typological analysis identified four different types of mechanical ventilation systems installed in three different classroom archetypes: wide, square and deep, with percentages of window area of 25%, 30% and 40 % respectively. The field measurement campaign showed that, in terms of CO2 concentration, mechanical ventilation was effective in the winter period, while in the mid-season and summer periods, natural ventilation was predominant due to the opening of windows by the occupants. Furthermore, in the case of manual control, incorrect use of the machine by the occupants, who reported noise-related problems or insufficient user training, resulted in CO2 levels above the recommended limits. Multivariate regressions developed for schools equipped with CMVs predicted maximum and average CO2 concentrations as a function of minimum and maximum indoor and outdoor temperatures with a significance (R2, correct) of 76 % and 83 % respectively
Monitoring and analysis of environmental and IAQ conditions in classrooms with controlled mechanical ventilation
Full text linkFollowing the health emergency from COVID-19, indoor air quality control has become of paramount importance, especially inside school buildings. For this reason, in 2021, the Marche region proposed and implemented an extraordinary intervention for the safe conduct of educational activities through the installation in classrooms of controlled mechanical ventilation systems aimed at air exchange. This type of system has been installed in more than 1,200 classrooms belonging to about 130 schools throughout the Marche region. This intervention made it possible to carry out a robust experimental measurement campaign on a significant number of classrooms where controlled mechanical ventilation systems were installed. Specifically, the work proposes a replicable measurement and analysis methodology for classrooms, with the aim of monitoring thermo-hygrometric and air quality conditions for environmental comfort. Thus, the research aims to implement knowledge on environmental comfort in classrooms equipped with controlled mechanical ventilation systems. The proposed measurements and analyses cover the most important environmental variables, i.e., air temperature, relative humidity, and CO2 concentration. In addition, measurements regarding system ventilation flow rates, smoke tests and evaluations of the permeability of classrooms
Experimental Comparison Between a Diffuse Insulation Masonry and a Traditional Lightweight Insulated Wall: Evaluation of Internal Temperatures and Thermal Comfort
No full textThe thermal masonry blocks are being introduced in building sector to replace traditional external thermal insulation composite systems due to the simplicity of their construction system, being set-up in a single-layer with the elimination of the insulating material. However, it is still unclear whether this new system is energy efficient, or whether the adoption of low thermal conductivity materials reduces the dynamic benefits of the thermal mass. This work presents an experimental study to evaluate the thermal behaviour of a new thermal masonry construction system, compared with a lightweight super-insulated system, by simultaneously measuring the thermal performance of two real house-like test rooms in an intermediate season and in summer. The results show the massive structure makes it possible to decrease the temperature of the internal air by 3.8 °C and 4.4 °C respectively in spring and in summer compared to the lightweight one, and to halve the hours of thermal discomfort
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Educational Buildings: Analysis of IAQ as a Function of Occupant Behavior and Mechanical Ventilation Systems
No full textFollowing the health emergency caused by SARS-CoV2, the MarcheRegion (Italy) implemented a series of interventions to finance mechanical ventilation systems in schools. These interventions enabled the implementation of ameasurement campaign to evaluate the functioning of mechanical ventilation insideeducational buildings. Specifically, the following study investigates the dynamicsregarding IAQ according to occupant behavior and the presence or absence of ventilation system on three different classrooms by analyzing the trend of measured CO2concentration. From the results obtained, it is evident that the classroom without aventilation system reaches much higher CO2 values than the classrooms with theventilation system, with a difference from the maximum values of 45.3%. In addition, the combination of natural ventilation and mechanical ventilation is crucial toobtain acceptable CO2 levels. These aspects are directly related to the behavior ofoccupants (opening/closing windows, using the ventilation system), who must beinformed about the various ventilation strategies and directed toward their conscioususe
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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